Avalanche victim locating transceiving apparatus

ABSTRACT

A rescue transceiver apparatus for transmitting a signal to and receiving a signal from another rescue transceiver apparatus is provided. The apparatus comprises a housing and a radio signal transmitter for the transmission of a radio signal in a transmitting mode with a first predetermined frequency with the radio signal transmitter being mounted within the housing. A receiver is provided for selectively receiving the first predetermined frequency from the radio signal transmitter in a receiving mode. The receiver comprises a first antenna mounted completely within the housing, a second antenna mounted completely within the housing with the second antenna being disposed substantially perpendicular to the first antenna, and a virtual third antenna mounted completely within the housing with the virtual third antenna being derived from phase information generated by the first antenna and the second antenna. The first antenna, the second antenna, and the third virtual third antenna provide three-dimensional vector analysis by the receiver of the predetermined frequency received from the radio transmitter. The apparatus further comprises a microcontroller for controlling the radio signal transmitter and the receiver.

The present application is a continuation of the pending provisionalpatent application entitled "Avalanche Victim Locating Apparatus", Ser.No. 60/035,675, filed on Jan. 22, 1997.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to an avalanche victim locatingtransceiving apparatus for locating buried victims by a searchingsurvivor and, more particularly, it relates to an avalanche victimlocating transceiving apparatus for locating buried victims by asearching survivor which provides both directional and distance readoutsto the searching survivor.

2. Description of the Prior Art

Avalanches pose an extremely grave danger for skiers, climbers, militarypersonnel, and others in mountain regions during winter and spring.Death or serious injury can result when a person is buried in snowunless rescue is quickly effected. Rescue is difficult because a personburied in an avalanche cannot be seen, may be moved by the avalancheaway from the last visible position, and cannot easily be located.Suffocation, hypothermia, and cardiac arrest, coupled with shock, becomemore likely the longer the victim is buried. The amount of time spent inlocating a victim is an important factor in the probability that thevictim will not survive or will be severely injured.

In an attempt to address these problems, electronic locating systems areincreasingly being used, for example, by the ski industry, snowmobilers,and the military. With one type of system presently in use, each memberof a group exposed to avalanche danger is supplied with a continuouslyenergized, battery powered radio transceiver unit operating continuouslyin a transmitting mode. With these known systems, continuoustransmission is relied upon to assure that transmission occurs when avictim is buried. If part of the group is buried in an avalanche, theremaining members switch their units to a receiving mode and attempt tolocate buried individuals by variations in received signal strength.

This type of system has serious drawbacks. Since the older units had tobe easily portable and battery weight was limited, the use of high poweralarm signals was impractical. These conventional units merely provideda non-directional signal. In order to find a buried victim, it isnecessary to move about, preferably in a grid pattern, while attemptingto detect increases and decreases in signal strength. This can bedifficult and time consuming, particularly in the unfavorable terraincommon to avalanche sites. The difficulty is compounded by the fact thatsurvivors are often confused or in shock. In addition, if multiplevictims are buried, the region of maximum signal strength may notcoincide with the location of a victim. In the prior art, powerconsumption and the necessity for continuous transmission prevent theuse of an audible alarm that would be useful when a survivor is inrelatively close proximity to a victim.

In an effort to overcome the shortcomings of the prior art, the Allsopet al, U.S. Pat. No. 4,850,031, describes an avalanche victim locatingsystem having a trigger provided by light sensitive elements on theuser, or by a signal transmitted from a survivor. A microprocessorcontrol synchronizes VHF information signal transmission and burstmicrowave transmission from a victim as well as received signalprocessing by a survivor. A directional multiple antenna array isswitched to provide directional signals displayed to the survivor and isextended when the apparatus is opened.

While the avalanche victim locating device of the Allsop et al patentovercomes many of the problems associated with the prior art, the deviceof the Allsop et al patent creates additional difficulties which must beaddressed. First, with the Allsop et al patent's device, it is notpossible to determine exactly the distance between the buried victim andthe searching survivor. Second, the device of the Allsop et al patentrelies on sensors to activate the unit to a transmitting mode. If thesensors are defective or become faulty, there is a chance that thetransmitting mode will never be activated. Third, even if the Allsop etal patent's device can be remotely activated by a rescuer, the rescuermust have the same device in order to activate the transmitting mode. Ifrescuers are using a different type of avalanche rescue device, theywill not be able to activate the transmitting mode and the buried victimwill not be able to be located. Finally, the device of the Allsop et alpatent relies on microwave technology which requires the size of therescue equipment to be quite large.

Accordingly, there exists a need for an avalanche victim locatingtransceiving apparatus for locating buried victims by a searchingsurvivor which provides both directional and distance readouts to thesearching survivor. Additionally, a need exists for an avalanche victimlocating transceiving apparatus for locating buried victims by asearching survivor which provides improved rescue times and decreasesthe amount of time the buried victim remains buried. Furthermore, thereexists a need for an avalanche victim locating transceiving apparatusfor locating buried victims by a searching survivor which provides dualvisual/audible functions for directional and versatility and backupredundancy for user confidence in all weather conditions. Further yet aneed exists for avalanche victim locating transceiving apparatus forlocating buried victims by a searching survivor which provides anefficient, tuned transmitter which automatically switches from a searchmode to a transmit mode in case of rescuers being caught in a secondaryavalanche while trying to locate the buried victims.

SUMMARY OF THE INVENTION

The present invention is a rescue transceiver apparatus for transmittinga signal to and receiving a signal from another rescue transceiverapparatus. The apparatus of the present invention comprises a portablehousing and a radio signal transmitter mounted within the housing forthe transmission of a radio signal in a transmitting mode with a firstpredetermined frequency. A receiver is provided for selectivelyreceiving the first predetermined frequency from the radio signaltransmitter in a receiving mode. The receiver comprises a first antennamounted completely within the housing, a second antenna mountedcompletely within the housing with the second antenna being disposedsubstantially perpendicular to the first antenna, and a virtual thirdantenna mounted completely within the housing with the third antennabeing derived from phase information generated by the first antenna andthe second antenna. The first antenna, the second antenna, and the thirdvirtual antenna provide three-dimensional vector analysis by thereceiver of the predetermined frequency received from the radiotransmitter.

In an embodiment of the present invention, the apparatus furthercomprises a microcontroller for controlling the radio signal transmitterand the receiver.

In another embodiment of the present invention, the first antenna andthe second antenna are selectively shielded and isolated. Preferably,the apparatus further comprises a tuned amplifier connected to the thirdantenna. Furthermore, preferably, the tuned amplifier has apredetermined frequency equal to the first predetermined frequency.

In still another embodiment of the present invention, the apparatuscomprises a superheterodyne receiver with the receiver receiving thefirst predetermined frequency, mixing the first predetermined frequencywith a local oscillator frequency, and generating an IntermediateFrequency for amplification, filtering, and generation of a logarithmicsignal strength.

In yet another embodiment of the present invention, the apparatuscomprises an activatable transmit/receive mechanism mounted to thehousing for selectively converting between the transmit mode and thereceiving mode. Preferably, upon activation of the transmit/receivemechanism from the transmit mode to the receiving mode, the apparatusautomatically converts from the receiving mode to the transmit modeafter a predetermined time period.

In still yet another embodiment of the present invention, the apparatuscomprises indication means on the housing for displaying information.Preferably, the indication means includes a dual digit, distance lightemitting diode display. Furthermore, preferably, the indication meansincludes a distance display displaying the distance between an apparatusin the transmit mode and an apparatus in the receiving mode.Additionally, preferably, the indication means includes a battery powerdisplay displaying the remaining battery power percentage of theapparatus.

In a further another embodiment of the present invention, the apparatuscomprises a plurality of indicators for determining direction between anapparatus in the transmit mode and an apparatus in the receiving mode.Preferably, the indicators are light emitting diodes arranged in an arcacross the housing.

In another embodiment of the present invention, the apparatus comprisesmeans for muting sounds emitting from the apparatus. Additionally, theapparatus comprises strapping means for releasably securing the housingto a person.

The present invention further includes a device for transmitting asignal to and receiving a signal from another device. The devicecomprises a housing and a radio signal transmitter for the transmissionof a radio signal in a transmitting mode with a first predeterminedfrequency, the radio signal transmitter being mounted within thehousing. A receiver is provided for selectively receiving the firstpredetermined frequency from the radio signal transmitter in a receivingmode and means for selectively masking multiple radio signaltransmissions are provided thereby allowing the receiver to selectivelyreceived one radio signal transmission.

The present invention also further includes a rescue transceiverapparatus for transmitting a signal to and receiving a signal fromanother rescue transceiver apparatus. The apparatus comprises a housingand a radio signal transmitter for the transmission of a radio signal ina transmitting mode with a first predetermined frequency with the radiosignal transmitter being mounted within the housing. A receiver isprovided for selectively receiving the first predetermined frequencyfrom the radio signal transmitter in a receiving mode and means areprovided for changing from the receiving mode to the transmitting modeafter a predetermined time period.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram illustrating an avalanche victimlocating transceiving apparatus for locating buried victims by asearching survivor constructed in accordance with the present invention;

FIG. 2 is a top view illustrating a plurality of directional LED's, adistance display, a closeness LED, an OPTIONS pad, and a transmit/searchpad of the avalanche victim locating transceiving apparatus for locatingburied victims by a searching survivor constructed in accordance withthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As illustrated in FIG. 1, the present invention is a an avalanche victimlocating transceiver apparatus, indicated generally at 10, for locatingvictims buried victims (not shown) carrying a transceiver apparatus 10by a searching survivor (not shown) carrying another transceiverapparatus 10. The transceiver apparatus 10 of the present inventionoffers a revolutionary novel manner and approach to avalanche rescuewith a transmit/search pad 48, as illustrated in FIG. 2, for control ofthe main features associated with the transceiver apparatus 10. A secondpad, OPTIONS 13, allows interface to other unique features of thetransceiver apparatus 10. As illustrated in FIG. 1, the apparatustransceiver 10 of the present invention utilizes state-of-the-art analogand digital technology combined with optimal transceiver design. Asevident from the novel features described heretofore and hereafter, thetransceiver apparatus 10 of the present invention decreases rescue timeswhile allowing extremely user friendly operation.

The transceiver apparatus 10 of the present invention has a firstantenna 12 mounted completely with a housing or protective enclosure 11and a second antenna 14 also mounted completely within the protectiveenclosure 11. The first antenna 12 is positioned at ninety degrees fromthe second antenna 14. The first antenna 12 and the second antenna 14are preferably constructed from a wire-wound ferrite material withcenter-tapped grounding, however, other suitable material known in theart for construction of the first antenna 12 and the second antenna 14is within the scope of the present invention. Preferably, the firstantenna 12 and the second antenna 14 have selective shielding andisolation 16, 18, respectively, by known means, including physicalgrounding, for improved performance and tracking capabilities of thetransceiver apparatus 10. Furthermore, the first antenna 12 and thesecond antenna 14 are capacitively tuned to 457 kHz.

A differential front end amplifier 20 of the transceiver apparatus 10provides a virtual third antenna 21 for the transceiver apparatus 10.The virtual third antenna 21 has a signal magnitude derived from thephase information generated by the differential front end amplifier 20.The magnitude information from the first antenna 12, the second antenna14, and front end amplifier 20, provides for three-dimensional vectoranalysis during rescue operations. Actual operation of the transceiverapparatus 10 of the present invention will be discussed in furtherdetail below.

The transceiver apparatus 10 further has a tuned amplifier 22 connectedto the differential front end amplifier 20. Preferably, the tunedamplifier 22 has a ceramic filter for image rejection. Similar to thefirst antenna 12 and the second antenna 14, the tuned amplifier 22 ispreset for 457 kHz Radio Frequency (RF). The present frequency (457 kHz)of the apparatus 10 is generally standard in the rescue industry and isthe same radio frequency used by other avalanche rescue devicesmanufactured by other companies. By utilizing the same radio frequencyas other devices, the transceiver apparatus 10 of the present inventionis usable to transmit and receive signals from other transceiver IIavalanche rescue devices for use in rescues whereby buried victims andrescuers are using a multitude of avalanche rescue devices manufacturedby other companies.

The transceiver apparatus 10 of the present invention also includes anupconversion mixer 24 to a higher frequency. The up-conversion isachieved through standard superheterodyne receiver techniques. The 457kHz RF output from the tuned amplifier 22 is applied to theup-conversion mixer 24. A local oscillator (LO) frequency of 4.036545MHz is heterodyned and the difference frequency of 3.579545 MHz is usedfor the Intermediate Frequency (IF). In short, the up-conversion 24allows improved Intermediate Frequency (IF) filtering.

The transceiver apparatus 10 has an efficient, crystal intermediatefrequency filter 26 and uses Received-Signal-Strength-Indicator (RSSI)28 with Low-Pass-Filtering 30 and digitizing of the RSSI 28. The RSSI isa logarithmic indication of signal strength. The signal islow-pass-filtered to reject extraneous noise, but still allowssufficient rise time to allow full processing. The output then goes toan Analog-to Digital converter (A/D) 32 for digitizing which iscontrolled by a microcontroller 34.

The transceiver apparatus 10 of the present unique invention includesthe common microcontroller or microprocessor 34 for controlling theoperation of the transceiver apparatus 10. Novel features of themicroprocessor include antenna switching, Digital Signal Processing(DSP) and filtering, three-dimensional vector analyses for directioninformation, diagnostics, improved human interface, linearization ofRSSI for distance display, automatic sensitivity adjustment, controlstransmitter (timing, enabling, etc.), automatic transmit defaultoperation, power supply control and maintenance (enabling, sleep, etc.).

The microcontroller 34 further includes multiple transmitter receptionselectivity for masking of extraneous signals received by thetransceiver apparatus 10 of the searching user from a multitude ofburied victims wearing any transmitter. The novel multiple transmitterreception selectivity capability for selective reception when there aremultiple transmitters being used such as when there are multiple buriedvictims is unique for the transceiver apparatus 10 of the presentinvention. The multiple transmitter selectivity of the present inventionenables the searching user of the transceiver apparatus 10 to clearlypinpoint one buried victim in case of multiple victim burials. Themicrocontroller 34 masks signals outside a window (betweenapproximately±three (3°) degrees to±five (5°) degrees) centered aboutthe middle of the flux path of a receiving transceiver apparatus 10.Therefore, the multiple transmitter selectivity of the transceivingapparatus 10 of the present invention allows the searching user to focuson only one buried victim at a time thereby masking the transceiverapparatuses 10 of the other buried victims until the first buried victimis recovered. By masking the transceiver apparatuses 10 of the otherburied victims, the searching user can quickly reach each buried victimin succession thereby decreasing the amount of time each victim isburied. The multiple transmitter selectivity feature is easily enteredby the searching user upon depression of the OPTIONS pad interface 13,as described above and will be described in further detail below.

Preferably, the transceiver apparatus 10 of the present invention alsoincludes down conversion 36 of Intermediate Frequency to audio frequencyand further amplification 38 to give increased range. The transmittingsignal direction and distance can now be inferred from the display onthe directional LED's (described below) and a piezoelectric speaker 40that has resonance at this audio frequency provides for improvedselectivity.

The transceiver apparatus 10 of the present invention further includesstable, accurate, crystal referenced system for transmit and anefficient, tuned transmitter driver 42. The microcontroller 34 controlsthe timing and operation of an oscillator 43 that is controlled by acrystal at eight (8) times 457 kHz, or 3.6560 MHz. The output from theoscillator goes to a transistor amplifier that is tuned to 457 kHz.

The transceiver apparatus 10 of the present invention is powered by asuitable power source 44 such as batteries or the like. For increasedsafety, each member of a group exposed to the possibility of avalanchedanger is provided with the transceiver apparatus 10 prior to enteringthe avalanche danger zone. Once the transceiver apparatus 10 isactivated, i.e., power on, the transceiver apparatus 10 is in thetransmit mode so that the signal is receivable by a searching user incase of accidental burial.

As mentioned, in operation of the transceiver apparatus 10 of thepresent invention, each user intending to hike, ski, snowmobile, etc. inan avalanche area will releasably secure one transceiver apparatus 10 onhis or her person. Each person can releasably secure the transceiverapparatus 10 to himself/herself by placing the transceiver apparatus 10in his/her pocket or with an included strapping system 70. Asillustrated in FIG. 2, the illustrated components of the transceiverapparatus 10 of FIG. 1 are preferably housed entirely within theportable housing or protective enclosure 11 to protect the components.In the preferred embodiment, the protective enclosure 11 has a length ofapproximately 5.5 inches, a width of approximately 3.25 inches, athickness of approximately one inch, and weighs approximately 8.5 ounces(241 grams).

The strapping system 70 is mounted to the protective enclosure 11 suchthat the user can easily strap the transceiver apparatus 10 about his orher person away from radios and other chest hardware and adjust thestrapping system 70 such that the transceiver apparatus 10 is snugagainst his or her abdomen. The unique strapping system 70 inhibitsaccidental dislodgment of the transceiver apparatus 10 during anavalanche or other burial event and is provided with a quick releasesystem providing fast, simple access when initiating search whilemaintaining the transceiver apparatus 10 attached to the searching userduring the search.

As mentioned above, the transceiver apparatus 10 normally operates in atransmit mode. In the event that one or more users are buried in anavalanche, the transceiver apparatuses 10 of each buried victim flash atransmit light 56 and continue to transmit a signal receivable by thetransceiver apparatuses 10 of by each of the survivors. To operate thetransceiver apparatus 10 in the search mode during location proceduresfor buried victims, the survivor or survivors will depress a manuallyoperated transmit/search pad 48 on the protective enclosure 11 toactivate the microprocessor 34 to the search mode. As a unique, addedsafety feature, the transceiver apparatus 10 of the present inventionrequires the searching survivor to depress the transmit/search pad 48 atpreset time intervals, e.g., every five minutes, or the transceiverapparatus 10 will automatically revert from the search mode to thetransmit mode. The unique automatic transmit feature of the transceiverdevice 10 provides victim-searching survivor transmit capabilities incase the survivor himself/herself becomes a buried victim of a secondaryavalanche while searching for the first buried victims and is not ableto manually activate the transceiver apparatus 10 to a transmit mode. Ina preferred embodiment, prior to expiration of the preset time interval,an alarm on the transceiver apparatus 10 activates to warn the searchingsurvivor to depress the transmit/search pad 48 to remain in the searchmode. By depressing the transmit/search pad 48 at the sound of thealarm, the preset time interval will be reset such that the transceiverapparatus 10 will remain in the search mode for an additional presettime interval upon which the transceiver apparatus 10 will revert backto the transmit mode.

To ease in location of the transceiver apparatus 10 of the buriedvictims, the transceiver apparatus 10 of the present invention furtherincludes a plurality of directional light emitting diodes (LED's) 50,51, 52, 53, 54 across one end of the transceiver apparatus 10, asillustrated in FIG. 2. The directional LED's 50-54 indicate thedirection of the transmitting flux lines from the transmittingtransceiver apparatus 10 providing a path to the transceiver apparatus10 of the buried victim. For instance, when the directional LED 50 isilluminated, it is an indication that the buried victim is in adirection generally toward the left of the searching survivor. When thedirectional LED 54 is illuminated, it is an indication that the buriedvictim is in a direction generally toward the right of the searchingsurvivor. Then, when the direction LED 52 is lit, adjacent the arrowindicator 57, it indicates that the buried victim is generally directlyahead or behind the searching survivor and the searching survivor canproceed in the correct direction of the buried victim without having tocoordinate complicated "tangent search" commonly used by prior artdevices. In fact, with the transceiver apparatus 10 of the presentinvention, no secondary "grid search" is required to pinpoint the buriedvictim at close range.

Furthermore, the transceiver apparatus 10 of the present inventionincludes a dual digit LED display 58 on the protective enclosure 11 fordisplaying information including, but not limited to, distanceinformation between the buried transceiver apparatus 10 of the buriedvictim to the searching transceiver apparatus 10 of the searching user.During the search, regardless of which directional LED 50-54 is lit, thetransceiver apparatus 10 of the searching survivor will have informationas to the distance of the transceiver apparatus 10 of the buried victimfrom the transceiver apparatus 10 of the searching survivor user.Distance information displayed on the distance display 58 of thetransceiver apparatus 10 of the present invention of the searchingsurvivor assists the searching survivor in quickly locating and rescuingthe buried victim thereby increasing the likelihood that the buriedvictim can be recovered prior to serious injury or death.

While the transceiver apparatus 10 is in the transmit mode, an LED 56flashes to indicate that the transceiver apparatus 10 is operational.Also, the transceiver apparatus 10 includes a speaker 40 which beepscoincident with the transmission in the transmit mode and which projectsthe alarm when the transceiver apparatus 10 is about to revert back tothe transmit mode from the search mode, as described above. Duringsearching mode, the transceiver apparatus 10 will also emit a sound fromthe speaker 40. When the searching user is within a predetermined range,e.g. three (3 m) meters, of the buried victim, the pitch of the soundfrom the speaker 40 will change indicating the closeness of thesearching user to the buried victim.

Furthermore, the transceiver apparatus 10 includes the OPTIONS padinterface 13 on the protective enclosure 13 for performing variousfunctions related to the operation of the transceiver apparatus 10. Forinstance, depressing the OPTIONS pad interface 13 for a predeterminedtime period allows the speaker to be muted. The OPTIONS pad interface 13further allows the user to convert the transceiver apparatus 10 into themultiple transmitter selectivity mode, as discussed above, and allowsthe remaining battery power to be displayed on the display 58, ifdesired.

It should be noted that it is within the scope of the present inventionthat the directional LED's and the distance display to be constructed ofa liquid crystal display (LCD) rather than an LED.

In sum, the transceiving apparatus 10 of the present invention digitizesthe signal from the transceiving apparatus 10 of the buried victim anddetermines the distance and direction of the buried victim. The rescueris then led directly to the buried victim's transceiver apparatus 10.The directional LED's 50-54 on the transceiving apparatus 10 indicatethe direction of travel and the distance display 58 on the transceiverapparatus 10 provides the distance to the buried victim. Thetransceiving apparatus 10 of the present invention virtually eliminatesconvoluted search patterns, earphones, and volume/sensitivity controlscommonly necessary in the prior art searching devices.

The foregoing exemplary descriptions and the illustrative preferredembodiments of the present invention have been explained in the drawingsand described in detail, with varying modifications and alternativeembodiments being taught. While the invention has been so shown,described and illustrated, it should be understood by those skilled inthe art that equivalent changes in form and detail may be made thereinwithout departing from the true spirit and scope of the invention, andthat the scope of the present invention is to be limited only to theclaims except as precluded by the prior art. Moreover, the invention asdisclosed herein, may be suitably practiced in the absence of thespecific elements which are disclosed herein.

We claim:
 1. A rescue transceiver apparatus for transmitting a signal toand receiving a signal from a different rescue transceiver apparatus,the apparatus comprising:a housing; a radio signal transmitter mountedwithin said housing for the transmission of a radio signal with a firstpredetermined frequency of about 457 kilohertz when said apparatus is ina transmit mode; a receiver mounted within said housing for selectivelyreceiving a radio signal with said first predetermined frequency from adifferent rescue transceiver apparatus when said apparatus is in areceiving mode, the receiver comprising: a first wire-wound loop antennamounted within the housing; a second wire-wound loop antenna mountedwithin the housing, the second wire-wound loop antenna being disposedsubstantially orthogonal to said first wire-wound loop antenna; meanswithin said housing for deriving a distance between said receiver and adifferent rescue transceiver apparatus and for deriving a direction fromsaid receiver to a different rescue transceiver apparatus wherein thederivations of distance and direction are derived only from signalsreceived by said first wire-wound loop antenna and said secondwire-wound loop antenna; and indication means on the housing fordisplaying information about a different rescue transceiver apparatus;wherein the indication means includes a distance display for displayingthe distance between a different rescue transceiver apparatus in thetransmit mode and the apparatus in the receiving mode.
 2. A rescuetransceiver apparatus for transmitting a signal to and receiving asignal from a different rescue transceiver apparatus, the apparatuscomprising:a housing; a radio signal transmitter mounted within saidhousing for the transmission of a radio signal with a firstpredetermined frequency of about 457 kilohertz when said apparatus is ina transmit mode; a receiver mounted within said housing for selectivelyreceiving a radio signal with said first predetermined frequency from adifferent rescue transceiver apparatus when said apparatus is in areceiving mode, the receiver comprising: a first wire-wound loop antennamounted within the housing; a second wire-wound loop antenna mountedwithin the housing, the second wire-wound loop antenna being disposedsubstantially orthogonal to said first wire-wound loop antenna; meanswithin said housing for deriving a distance between said receiver and adifferent rescue transceiver apparatus and for deriving a direction fromsaid receiver to a different rescue transceiver apparatus wherein thederivations of distance and direction are derived only from signalsreceived by said first wire-wound loop antenna and said secondwire-wound loop antenna; sound generation means for projecting a soundduring the receiving mode, the pitch of the sound changing as saidapparatus when in the receiving mode, approaches a different rescuetransceiver apparatus that is in the transmitting mode; and means formuting said sound generation means.
 3. An apparatus comprising:areceiver for selectively receiving a radio signal with a firstpredetermined frequency from a radio signal transmitter, the receivercomprising:a first electrically small loop antenna; and a secondelectrically small loop antenna disposed substantially orthogonal tosaid first electrically small loop antenna; a microcontroller coupled tosaid receiver for deriving information regarding distance and directionto said radio signal transmitter relative to said apparatus wherein saidinformation is derived only from magnitudes of signals generated by saidfirst electrically small loop antenna in response to receiving a radiosignal with said first predetermined frequence and said secondelectrically small loop antenna in response to receiving a radio signalwith said first predetermined frequency; and display means coupled tosaid microcontroller for displaying information regarding distance anddirection from said apparatus to a radio signal transmitter; whereinsaid display means includes a plurality of directional indicatorscoupled to said microcontroller operably controlled by saidmicrocontroller to indicate a most likely direction to a radiotransmitter relative to the apparatus; wherein said plurality ofdirectional indicators comprises:a center indicator indicative of aradio transmitter being along an extension of a center line axis of saidapparatus relative to a present orientation of said apparatus; at leastone right indicator indicative of a radio transmitter being rightwardfrom said centerline axis of said apparatus relative to a presentorientation of said apparatus; and at least one left indicatorindicative of a radio transmitter being leftward from said centerlineaxis of said apparatus relative to a present orientation of saidapparatus.
 4. The apparatus of claim 3 wherein each of said plurality ofdirectional indicators is a light emitting diode illuminated to indicatea corresponding direction.
 5. An apparatus comprising:a receiver forselectively receiving a radio signal with a first predeterminedfrequency from a radio signal transmitter, the receiver comprising:afirst electrically small loop antenna; and a second electrically smallloop antenna disposed substantially orthogonal to said firstelectrically small loop antenna; a microcontroller coupled to saidreceiver for deriving information regarding distance and direction to aradio signal transmitter relative to said apparatus wherein saidinformation is derived only from magnitudes of signals generated by saidfirst electrically small loop antenna in response to receiving a radiosignal with said first predetermined frequency and the secondelectrically small loop antenna in response to receiving a radio signalwith said first predetermined frequency; and display means coupled tosaid microcontroller for displaying information regarding distance anddirection from said apparatus to a radio signal transmitter; whereinsaid display means includes a digital display coupled to saidmicrocontroller and that is operably controlled by said microcontrollerto display digital information relating to a radio transmitter andrelating to said apparatus; wherein said digital display is operablycontrolled by said microcontroller to display a distance from saidapparatus to a radio transmitter.
 6. An apparatus comprising:a receiverfor selectively receiving a radio signal with a first predeterminedfrequency from a radio signal transmitter, the receiver comprising:afirst electrically small loop antenna; and a second electrically smallloop antenna disposed substantially orthogonal to said firstelectrically small loop antenna; a microcontroller coupled to saidreceiver for deriving information regarding distance and direction to aradio signal transmitter relative to said apparatus wherein saidinformation is derived only from magnitudes of signals generated by saidfirst electrically small loop antenna in response to receiving a radiosignal with said first predetermined frequency and said secondelectrically small loop antenna in response to receiving a radio signalwith said first predetermined frequency; display means coupled to saidmicrocontroller for displaying information regarding distance anddirection from said apparatus to a radio signal transmitter; and a soundgenerator coupled to said microcontroller and operably controlled bysaid microcontroller to alter the pitch of a sound generated by saidsound generator in proportion to the distance between said apparatus anda radio transmitter; wherein said receiver includes a superheterodynereceiver for receiving a first signal with said first predeterminedfrequency and for mixing said first signal with a local oscillatorsignal with a second predetermined frequency to generate a first productsignal with a first Intermediate Frequency, and wherein the apparatusfurther comprises:a down converter circuit associated with said soundgenerator for producing a second product signal with a secondIntermediate Frequency and having an amplitude proportional to thedistance and direction from said apparatus to a radio signal transmitterwherein said second product signal is directly applied to said soundgenerator to produce an audio signal having an amplitude indicative ofsaid distance and direction from said apparatus to a radio signaltransmitter.
 7. An apparatus comprising:a receiver for selectivelyreceiving a radio signal with a first predetermined frequency from aradio signal transmitter, the receiver comprising:a first electricallysmall loop antenna; and a second electrically small loop antennadisposed substantially orthogonal to said first electrically small loopantenna; a microcontroller coupled to said receiver for derivinginformation regarding distance and direction to a radio signaltransmitter relative to said apparatus wherein said information isderived only from magnitudes of signals generated by said firstelectrically small loop antenna in response to receiving a radio signalwith said first predetermined frequency and said second electricallysmall loop antenna in response to receiving a radio signal with saidfirst predetermined frequency; and display means coupled to saidmicrocontroller for displaying information regarding distance anddirection from said apparatus to a radio signal transmitter; whereinsaid receiver includes a superheterodyne receiver for receiving a firstsignal with said first predetermined frequency and for mixing said firstsignal with a local oscillator signal with a second predeterminedfrequency to generate a first product signal with a first IntermediateFrequency, and wherein the apparatus further comprises:a down convertercircuit associated with said microcontroller for producing a secondproduct signal with a second Intermediate Frequency and having anamplitude proportional to the distance and direction from said apparatusto a radio signal transmitter wherein said second product signal isapplied to said microcontroller to produce a display indicative of saiddistance on said display means.
 8. An apparatus for use in rescueoperations, the apparatus comprising:a housing; a receiver comprising:afirst antenna for receiving a radio signal having a predeterminedfrequency and in response to the radio signal, producing a firstelectrical signal; a second antenna for receiving a radio signal havingsaid predetermined frequency and in response to the radio signal,producing a second electrical signal; wherein said first antenna andsaid second antenna are the same type of antenna; a microcontroller forusing information derived from said first electrical signal and saidsecond electrical signal to determine a distance between a source of theradio signal and said housing and a direction of the source of the radiosignal relative to said housing; and an interface for providing a userwith an indication of said distance and said direction.
 9. An apparatus,as claimed in claim 8, wherein:said first antenna and said secondantenna are both wire-wound loop antennas.
 10. An apparatus, as claimedin claim 8, wherein:said first antenna and said second antenna are bothwire-wound ferrite antennas.
 11. An apparatus, as claimed in claim 8,wherein:said first antenna and said second antenna are both tuned to 457kHz.
 12. An apparatus, as claimed in claim 8, wherein:said first antennahas a first longitudinal axis; said second antenna has a secondlongitudinal axis; and said first longitudinal axis is at an angle tosaid second longitudinal axis.
 13. An apparatus, as claimed in claim 8,wherein:said first antenna has a first longitudinal axis; said secondantenna has a second longitudinal axis; and said first longitudinal axisis substantially orthogonal to said second longitudinal axis.
 14. Anapparatus, as claimed in claim 8, wherein:said microcontroller usesmagnitude information derived from said first electrical signal and saidsecond electrical signal to determine said distance.
 15. An apparatus,as claimed in claim 8, wherein:said housing has a thickness of less thanapproximately one inch.
 16. An apparatus for use in rescue operations,the apparatus comprising:a housing; a receiver comprising:a firstantenna for receiving a radio signal having a predetermined frequencyand in response to the radio signal, producing a first electricalsignal; a second antenna for receiving a radio signal having saidpredetermined frequency and in response to the radio signal, producing asecond electrical signal; a differential amplifier having a first inputfor receiving said first electrical signal, a second input for receivingsaid second electrical signal, and an output for providing a thirdsignal that is representative of the difference in magnitudes betweensignals received at said first and second inputs; a microcontroller forusing information derived from said first electrical signal, said secondelectrical signal, and said third electrical signal to determine adistance between a source of the radio signal and said housing and adirection of the source of the radio signal relative to said housing;and an interface for providing a user with said distance and saiddirection.
 17. An apparatus, as claimed in claim 16, wherein:saidreceiver includes a first switch for selectively providing said firstelectrical signal to said differential amplifier and a second switch forselectively providing said second electrical signal to said differentialamplifier.
 18. An apparatus, as claimed in claim 16, wherein:saidreceiver includes means for providing a logarithmic indication of themagnitude of said third electrical signal.
 19. An apparatus, as claimedin claim 18, wherein:said microcontroller includes means for linearizingsaid logarithmic indication related to said third electrical signal. 20.An apparatus, as claimed in claim 16, wherein:said interface includes avisual interface for providing one of the following: distance anddirection.
 21. An apparatus, as claimed in claim 16, wherein:saidinterface include a visual interface for providing both distance anddirection.
 22. An apparatus, as claimed in claim 16, wherein:saidinterface includes a visual reference relative to which directioninformation is provided.
 23. An apparatus, as claimed in claim 22,wherein:said interface includes a first visual direction indicator thatis located to one side of said visual reference and a second visualdirection indicator that is located to the opposite side of said visualreference.
 24. An apparatus, as claimed in claim 16, wherein:saidinterface includes a visual distance display for displaying a distancefrom said receiver to the source of the radio signal.
 25. An apparatus,as claimed in claim 16, wherein:said interface includes an audio speakerfor providing audio information indicative of a least one of thefollowing: (a) a distance between a transmitter and said receiver; and(b) a direction of a transmitter relative to said receiver.
 26. Anapparatus, as claimed in claim 16, wherein:said interface includes anaudio speaker for providing audio information indicative of a distancebetween the source of the radio signal and said receiver and a directionof a source of the radio signal relative to said receiver.
 27. Anapparatus, as claimed in claim 16, wherein:said interface includes meansfor adjusting the volume of an audio speaker.
 28. An apparatus, asclaimed in claim 16, wherein:said receiver and said microcontroller aremounted within said housing.